Phonographic stylus



Dec. 18,1923. 1,478,192

v R. c. WADE PHONOGRAPHIC STYLUS Filed Sent. 1919 reams Dec. is, 1923.;

eanenniren sitar earner coerce.

ROBERT C. WADE}, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE TdIJOFONECOITIPANY, A

CORPORATION OF ILLINOIS.

PHONOGRAPHIC STYLUS.

Application filed September 2, 1919. Serial No. 321,218.

To aZZ whom it may concern:

Be it known that 1, ROBERT C. WADE, a citizen of the United States,residing at the city of Chicago, in the county of Cook and State ofIllinois, have invented certain new and useful Improvements inPhonographic Styli, of which the following is a specification.

uniform rigidity My invention relates to the devices by which soundrecords are made audible in sound reproducing machines and it hasparticularly to do with the needles or styli which are used in thatconnection, and with the construction and character thereof.

The effect of all standard needles or styli as attached to the sound boxof a sound reproducing machine is that of a substantially throughouttheir length the bearing end thereof operating in the record groovewhich has an almost infinite number of projections or undulations.- Andthere has been theory and practice to the effect that the bearing endshould be of hard material relatively to the reproduction inequalitiesof the sound record. But while that portion of a stylus which is clampedto the sound box should be adapted to solid and nonvibrating connectiontherewith, T have discovered that it is also important that the soundreproducing portion, that which comes in operative contact with thesound record, Should be soft in quality and resilient in action.

In my invention I have, therefore, provided a composite stylus in whichthe shank or holding member and the point 'or reproducing member haveesentially difierent physical characteristics. That portion which is inimmediate relation to the record is adapted to conform itself to thegeneral style of groove used, and it is also elastic or resilient sothat it will follow tions on the records of any standard construction.

That portion of the stylus in which the bearing end is mounted is arelatively large and rigid structure and its action is not that ofconforming itself to the inequalities or undulations of the record butof receiving and transmitting the vibrations of the resilient member tothe sound box.

- The principles of my invention are illustrated in the drawings inwhich Fig. 1 represents my improved stylus in approximately naturalsize. Fig. 2shows the same the undulaof within certain greatly enlarged,Fig. 3 represents the resilient member still further enlarged inrelation to a section of a phonographic record.

Further describing my invention with reference to the drawings, 1 is theresilient member which is in contact with the record and is adapted toride in the grooves thereof. It is securely fastened into the holdingmember or shank 2, which further may provided with the head 3 and flange4:- The stylus may be constructed in many ways, but

it is important to secure the sensitive resilient point in thenonresilient and relativelylarge and heavy shank to which for furthersolidity may be added the enlarged portions of the head and flange.

It is diflicult to illustrate graphically the great disparity ofthickness and weight between the resilient point and the portion onwhich it is mounted. I willhowever, say that in practice the resilientmember consists of spring wire of suitable character as to softness andof a diameter approximately .007 of an inch. The shank wire which isadapted for general use and to be received within the clamping membersof sound boxes as ordinarily constructed may be any suitable material ofa diameter approx1- mately .067 of an inc I prefer to make the shank ofbrass or copper wire and to so treat it that it will be very soft inquality. This is for the double purpose of causing it to form readilyand securely about the vinserted point and of eliminating anyspringiness which might give rise to external vibrations, and withoutinterferin with -its sound conductivity. This quality aids materially ineliminatng the so-called needle sing which is present in styli which areof homogeneous quality throughout their length.

In the process of manufacture the members are united in any suitableway. A slit, indentation or other opening may be in the soft metal blankfrom which the shank is made. One end of the resilient member isinserted in the opening and the edges of the shank member are thenswaged in suitable dies down upon the resilient member. I prefer to havethe dies so constructed that the thickness of the-shank adjacent to theinserted member is substantially increased forming the head 3.- Theformation of this head is not absolutely essential and the sizetherelimits is not greatly material, but it does add stren to theconstruction and it a and non-vibrative character of the structurerelatively to the resilient member mounted thereon. In practice I preferto make the greatest diameter of the head 3 about .09 of an inch indiameter and that of the flange 4 about .125 of an inch.

It further should be noted that the resilient member should be made ofwire of uniform diameter cut squarely across the lower end so thatthe'latter shall form a h and security ds to the weight of this portionplane at substantially right angles to the should be of such which wouldescape'a more longitudinal axis of the W1re. The reproducing styliofsound reproducing machines are usually inclined to the record at anangle of about The spring or elastic contactmember of my invention is ofa diameter fairly corresponding to the width of the record grooves. Itsrelation thereto is illustrated in .Fig. 3 in which 6 is the plane faceof the elastic member 1 As the record is started'moving under the stylusthe latter will ride upon the thin edges 7 of the plane face.

The material of the contact member quality as to softness that it willreadily be shaped to the general formation of the record groove by theabrasive properties of the record material. When the record startsrevolving, the spring contact member will immediately assume the properform and settle into the groove. It is immaterial whether the roove isof the vertical or lateral type.' fts elasticity .will enable it, whilethe record is revolving, to follow the exact contour of the groovesIII'QSPGOiJiVG of the class to which the groove belongs. That is, itwill traverse the exact profile of each undulation therein and thusconduct through the shank to the sound box, the reproduction of everyoriginal sound vibration as recorded by such undulations.

vAn even and uniform tone is thus produced,

and matter in the sound record is developed rigid reproduc- And thecharacter of the mation point.-

prevent the scratching sounds terial will which are and by those whichare comparatively inflexible in character.

As the contact member is of uniform diameter a large number of recordsmay be played before the available length of the contact member isexhausted. In fact, the entire wire may be jury to the record which maybe played to such time as the soft metal shank will ride on the surfaceof the record. But this is not advisable or contemplated in myinvention, for the resilient quality of the contact member will be lostwhen it becomes excessively shortened by wear.

1. In a phonograph stylus, a highly resilient tip member adapted toengage the sound record record, the pro ecting portion of said tipmember being of comparatively great length and of a diametersubstantially corresponding to the width of the widest part of therecord groove, said resilient member being of soft material capable ofbeing readily shaped to the grooves of a phonograph record.

2. phonograph stylus comprising a highly resilient tip member adapted toengage the sound record groove of a phonograph record, the projectingportion of said tip member being of comparatively great length and of adiameter substantially corresponding to the width of the widest part ofthe record groove, said resilient member being of soft material capableof being readily shaped to the grooves of a phonograph record, and ashank of relative] softnonvibrative material in which said tip member isaxially fixed.

In witness whereof, I have hereunto subscribed my name this 29th day ofAugust, 1919, at Chicago, Cook Count Illinois.

ROBERT C. WADE.

produced by solid stylus points worn away without ingroove of aphonograph

